Jezard cannot remember how he did it because he was too drunk at the time, a court heard on Wednesday.

When his initial co-pilot response didn't get much traction with the cleaners, he tried to explain he worked for the Navy. But the cleaners weren't buying that either and he eventually confessed to his crime and was arrested by airport police.

He told officers: "I was trying to show how easy it was to get on that plane - and I did it. I told the cleaners I was the co-pilot."

He struggled to recall everything that had happened, telling police he "wanted a walk around and thought it would be a good idea".

Security cameras showed Jezard crawling through the opening of a baggage carousel, getting on to the airport's tarmac apron, and then getting aboard the plane.

Lee Jezard pleaded guilty to boarding the Lufthansa aeroplane at Birmingham airport in July, and to stealing £36.45 ($65) in items from an airport cafe.

Birmingham magistrates fined Jezard – who also lost his job as a hotel manager after the incident – £95 ($A170) for each of the three offences.

He was also ordered to pay full compensation to the coffee shop, together with £185 ($A331) of costs and a £20 ($A36) victim surcharge.

Jezard's defence lawyer said his client had little recollection of how he had arrived at the airport after a night drinking with friends in Birmingham city centre.

It was initially reported Jezard had missed a flight to Ibiza but after a police examination of flight bookings it was found he was never booked on a flight.

Khan said although it was a relatively low-level security breach, the incident had implications beyond Jezard's drunken activities.

"I am sure airport staff and management will have been having a close look at events, and security will have been tightened up, because of the implications this could have been a more serious breach than it was in this case," he said.

However, aviation sources told the Mirror it was "one of the biggest security breaches at a British airport".

Police prosecutor David Devine said Jezard's response to the cleaners was that he had done similar things in the past

"He said: I'm breaking into places to see if people can catch me - I go to prisons and other places," Devine said.

The prosecution said Jezard had told had told cleaning staff who discovered him on the plane "I'm the co-pilot", and described the incident as a "drunken escapade".